JP2007314416A - Composite - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new microcomposite which can give a strong material or a reinforcement, a diffusion prevention layer, an extraction prevention layer, an oxidation protection layer, and an electrical insulation layer to a substrate. <P>SOLUTION: A composite material comprises a substrate and a microcomposite in contact with the substrate, wherein the substrate is selected from the group consisting of glass or mineral in the shape of granules, floc, flakes, plates, foil, sheets, laminates or moldings. Microcomposite sol is formed by a sol-gel process using (a) colloidal inorganic particles, (b) one or more silanes, and 0.1-0.45 mol% of water per mole of a hydrolyzable group present. The microcomposite sol is further hydrolyzed and condensed, and then activated by further adding water. The surface of the composite material is modified by curing of the activated microcomposite sol. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a composite material whose surface is modified by a fine composite sol using glass or mineral as a substrate.

The present invention is a particle-like, cotton-like, Katakatachi, plate-shaped, and the foil-shaped, formed molded article substrate and the substrate is selected from the group consisting of glass or mineral shape (sheet or block, including a laminate) Characterized by contacting microcomposites, and a) colloidal inorganic particles;
b) one or more general formulas (I)
R _x -Si-A _4-x (I)
[Where:
Group A is the same or different and one or more hydroxyl groups other than methoxy that can be removed hydrolytically, Group R is the same or different and cannot be removed hydrolytically, and x is 0, 1, 2 or 3, where x> 1 in at least 50 mol% of the silane]
Of the silane in a sol-gel process using 0.1 to 0.45 mole percent water per mole of hydrolyzable groups present, further hydrolysis and condensation of the microcomposite sol, The present invention relates to a composite material surface-modified by the activation of a microcomposite sol with addition of water and subsequent curing.

Substrates made of glass and minerals can be in a great variety of physical forms and are, for example, granular, cotton-like , plate- like, foil-like, sheet-like Or a block shape, or a laminated structure, or a molded product having any desired shape. The term “granular” includes powders, fines, granules, pieces, strips, droplets, globules and particles that generally have a regular or irregular shape.

Microcomposites can also exist in a variety of forms. It may, for example, completely or partially cover the substrate as a continuous coating or cover, or may be similar to a laminate between multiple substrates . Infinitesimal composite TsuyoTsuyoshizai or reinforcements, anti-diffusion layer, extraction-preventing layer, oxidation protective layer, can be used as an electrical insulating layer or planarizing.

Nanocomposite is or forms the contact of discrete or point-shaped between multiple substrates, and, for example granular, as in the insulating material, also act as a matrix in coupling cotton-like base substance it can.

Incidentally, minerals, for example montmorillonite, bentonite, mica, vermiculite, pearlite, ferrite, spinel, such magnetite or copper chromium spinel, barite, fluorite, is asbestos, talc, aerogels, sand and clay .

  The microcomposites used in accordance with the present invention are (a) one or more silanes (b) in the presence of other additives if desired (c) colloidal under the conditions of the sol-gel process Manufactured by surface modification of inorganic particles.

  Details of the sol-gel method can be found in CJ Brinker, GW Scherer: “Sol-Gel Science-The Physics and Chemistry of Sol-Gel-Processing”, Academic Press, Boston, San Diego, New York, Sydney (1990) and DE 1941191, DE 37 19 339, DE 40 20316 and DE 4217432.

  Shown here are individual examples of silanes (b) that can be used according to the invention and their radicals A that are hydrolytically removable and radicals R that are not hydrolytically removable.

Suitable examples of the group A which can be removed hydrolytically are hydrogen, halogen (F, Cl, Br and I, especially Cl and Br), alkoxy (especially C _2-4 -alkoxy, such as ethoxy, n-propoxy, Isopropoxy and butoxy), aryloxy (especially C _6-10 -aryloxy, eg phenoxy), alkaryloxy (eg benzyloxy), acyloxy (especially C _1-4 -acyloxy, eg acetoxy and propionyloxy) and alkylcarbonyl (For example, acetyl). Likewise suitable groups A are amino groups (for example mono- or dialkyl-, -aryl- and -aralkylamino groups with alkyl, aryl and aralkyl groups as described above), amide groups (for example benzamide) and aldoxime or ketosim groups. Two or three groups A may be taken together to form a moiety that complexes Si atoms, for example in Si-polyol complexes derived from glycol, glycerol or pyrocatechol. A particularly preferred group A is a C _2-4 -alkoxy group, especially ethoxy. Since methoxy groups have excessively high reactivity (short processing time of microcomposite sols) and can give microcomposites and / or composites with insufficient flexibility, they are for the purposes of the present invention. Is not very suitable.

  The hydrolyzable group A may have one or more common substituents, such as halogen or alkoxy, if desired.

Hydrolytically non-removable radicals R are preferably alkyl (especially C _1-4 -alkyl, eg methyl, ethyl, propyl and butyl), alkenyl (especially C _2-4 -alkenyl, eg vinyl, 1-propenyl, 2-propenyl and butenyl), alkynyl (especially C _2-4 -alkynyl, such as acetylenyl and propargyl), aryl (especially C _6-10 -aryl, such as phenyl and naphthyl) and the corresponding alkaryl and arylalkyl groups Selected from. These groups may have one or more common substituents, such as halogen, alkoxy, hydroxy, amino or epoxide groups, if desired.

  The above alkyl, alkenyl and alkynyl groups include the corresponding cyclic groups such as cyclopropyl, cyclopentyl and cyclohexyl.

Particularly preferred groups R are substituted or unsubstituted C _1-4 -alkyl groups, especially methyl and ethyl, and substituted or unsubstituted C _6-10 -alkyl groups, especially phenyl.

  It is also preferred that x in the above formula (I) is 0, 1 or 2, particularly preferably 0 or 1. It is also preferred that x = 1 in at least 60 mol%, in particular at least 70 mol% of the silane of formula (I). In special cases, it is even more preferred that x = 1 in more than 80 mol% or more than 90 mol% (eg 100 mol%) of the silanes of formula (I).

  The novel composite material can be produced, for example, from pure methyltriethoxysilane (MTEOS) or a mixture of MTEOS and tetraethoxysilane (TEOS) as component (b).

  The use of silanes with one or more substituted groups R is recommended, especially when trying to give special properties to the composite material. For example, the introduction of fluorine atoms (eg in the form of substituted aliphatic (especially alkyl) groups) can give composites with water-, dirt-, dust- and oil-repellency.

Specific examples of silanes of general formula (I) are compounds of the following formula:
Si (OC ₂ H ₅ ) ₄ , Si (On- or iso-C ₃ H ₇ ) ₄ , Si (OC ₄ H ₉ ) ₄ , SiCl ₄ , Si (OOCCH ₃ ) ₄ ,
CH ₃ -SiCl ₃ , CH ₃ -Si (OC ₂ H ₅ ) ₃ , C ₂ H ₅ -SiCl ₃ , C ₂ H ₅ -Si (OC ₂ H ₅ ) ₃ , C ₃ H ₇ -Si (OC ₂ H ₅ ) ₃ , C ₆ H ₅ -Si- (OC ₂ H ₅ ) ₃ , C ₆ H ₅ -Si (OC ₂ H ₅ ) ₃ , (C ₂ H ₅ O) ₃ -Si-C ₃ H ₆ -Cl , (CH ₃ ) ₂ SiCl ₂ , (CH ₃ ) ₂ Si (OC ₂ H ₅ ) ₂ , (CH ₃ ) ₂ Si (OH) ₂ , (C ₆ H ₅ ) ₂ SiCl ₂ , (C ₆ H ₅ ) ₂ Si (OC ₂ H ₅ ) ₂ , (C ₆ H ₅ ) ₂ Si (OC ₂ H ₅ ) ₂ , (iso-C ₃ H ₇ ) ₃ SiOH, CH ₂ = CH-Si (OOCCH ₃ ) ₃ , CH ₂ = CH-SiCl ₃ , CH ₂ = CH-Si (OC ₂ H ₅ ) ₃ , HSiCl ₃ , CH ₂ = CH-Si (OC ₂ H ₄ OCH ₃ ) ₃ ,
CH ₂ = CH-CH ₂ -Si (OC ₂ H ₅ ) ₃ , CH ₂ = CH-CH ₂ -Si (OOCCH ₃ ) ₃ ,
CH ₂ = C (CH ₃ ) COO-C ₃ H ₇ -Si- (OC ₂ H ₅ ) ₃ , CH ₂ = C (CH ₃ ) -COO-C ₃ H ₇ -Si (OC ₂ H ₅ ) ₃ ,
nC ₆ H ₁₃ -CH ₂ -CH ₂ -Si (OC ₂ H ₅ ) ₃ , nC ₈ H ₁₇ -CH ₂ -CH ₂ -Si (OC ₂ H ₅ ) ₃ ,

  These silanes can be prepared by known methods; see W. Noll, “Chemie and Technologie der Silicone” [Chemistry and Technology of the Silicones], Verlag Chemie GmbH, Weinheim / Bergstrae, Germany (1968).

Formula prepared by condensation based on the above components (a), (b) and (c):
The proportion of component (b) represented as polysiloxane of R _x SiO 2 _(2-0.5x) is generally 20 to 95% by weight, preferably 40 to 90% by weight and particularly preferably 70 to 90% by weight. %.

  The silanes of general formula (I) used according to the invention are in the form of precondensates, ie compounds prepared by partial hydrolysis of silanes of formula (I), alone or in other hydrolysable compounds Can be used in whole or in part. Such oligomers which are preferably soluble in the reaction medium are, for example, linear or cyclic low molecular weight partial condensates (polyorganosiloxanes) having a degree of condensation of about 2-100, in particular about 2-6. It may be.

  The amount of water used for hydrolysis and condensation of the silane of formula (I) is 0.1 to 0.45 moles per mole of hydrolyzable groups present.

Individual examples of colloidal inorganic particles (a) are nano-level (preferably up to 300 nm, in particular up to 100 nm and particularly preferably up to 50 nm) SiO ₂ , TiO ₂ , ZrO ₂ , Al ₂ O ₃ , Sol and dispersible powders of Y ₂ O ₃ , CeO ₂ , SnO ₂ , ZnO, iron oxide or carbon (carbon black and graphite), especially SiO ₂ .

  Based on components (a), (b) and (c), the proportion of component (a) is generally 5 to 60% by weight, preferably 10 to 40% by weight and particularly preferably 10 to 20% by weight. %.

  In order to produce microcomposites, other additives in amounts up to 20% by weight, preferably up to 10% by weight and in particular up to 5% by weight can be used as optional component (c). Examples thereof are curing catalysts such as metal salts and metal alkoxides (eg aluminum alkoxide, titanium alkoxide or zirconium alkoxide), organic binders such as polyvinyl alcohol, polyvinyl acetate, starch, polyethylene glycol and gum arabic, pigments, dyes, Flame retardants, glass manufacturing elements (such as boric acid, boric acid esters, sodium methoxide, potassium acetate, aluminum sec-butoxide), corrosion inhibitors and coating aids. According to the present invention, the use of a binder is less preferred.

  Hydrolysis and condensation are carried out under sol-gel conditions in the presence of an acid condensation catalyst (eg hydrochloric acid), preferably at a pH of 1-2, until a sticky sol is produced.

  It is preferred that no additional solvent be used in addition to the solvent produced by hydrolysis of the alkoxy group. However, if desired, alcoholic solvents such as ethanol, or other polar protic or aprotic solvents such as tetrahydrofuran, dioxane, dimethylformamide or butyl glycol may be used, for example.

  In order to obtain the preferred sol particle morphology and sol viscosity, the resulting microcomposite sol is preferably subjected to a special post-reaction stage, in which the reaction mixture is heated to a temperature of 40-120 ° C. over a period of hours to days. . Particular preference is given to storage for one day at room temperature or heating for several hours at 60-80 ° C. This gives a microcomposite sol having a viscosity of preferably 5 to 500 mPas, particularly preferably 10 to 50 mPas. Of course, the viscosity of the sol can be adjusted to a value suitable for a particular application by adding a solvent or by removing reaction by-products (eg alcohol). The post reaction step may preferably be combined with a reduction of the solvent content.

  The weight proportion of the microcomposite in the composite material is preferably 0.1 to 80% by weight, in particular 1 to 40% by weight and particularly preferably 1 to 20% by weight.

  The substrate and the microcomposite or microcomposite sol are combined at least after the initial hydrolysis of component (b) and in each case before final curing. Prior to contacting it with the substrate, the microcomposite sol is preferably activated by feeding it into another amount of water.

  Contact in or with a microcomposite sol is known to those skilled in the art and may be useful in certain cases, for example by simply mixing the substrate and the microcomposite sol. Dipping, spraying or showering, knife- or spin-coating, pouring, spreading, brushing, etc. In order to improve the adhesion between the substrate and the microcomposite, a general surface pretreatment such as corona discharge; degreasing; primer such as aminosilane, epoxy before contacting the substrate with the microcomposite or its precursor It is often advantageous to subject the treatment to a sizing agent, a complexing agent, a surfactant made from silane, starch or silicone.

  Prior to final curing, a drying step may be performed at room temperature or slightly elevated temperature (eg, up to about 50 ° C.).

The actual curing or precuring can be carried out at room temperature, but can be suitably carried out by heat treatment at temperatures above 50 ° C., preferably above 100 ° C. and particularly preferably at 150 ° C. or higher. The maximum curing temperature depends on the melting point and / or heat resistance of the substrate, but is generally 250 to 300 ° C. However, for metal or mineral substrates, fairly high curing temperatures are possible, for example 400-500 ° C. and higher. Curing may be carried out in an inert gas atmosphere (eg N ₂ , argon) if desired, especially if the substrate is easily oxidized. The curing time is generally in the range of several minutes to several hours, for example 2 to 30 minutes.

  In addition to general curing by heat (eg in a circulating air oven), other curing methods are used, such as photochemical curing (UV-VIS), electron beam curing, rapid annealing and curing using infrared or laser radiation. May be.

  If desired, the manufactured composite may be subjected to a molding step prior to curing.

  The invention also relates to the use of the microcomposites described above for coating and / or integration of the substrates described above. The term “integrated” is intended here to include means suitable for providing an integrated and / or consolidated form of the substrate, and thus, for example, impregnation of the microcomposite into the substrate, microcomposite Embedding the substrate in the matrix of the object or immobilizing or binding the substrate or substrate piece with the microcomposite. The term “coating” specifically refers to a microcomposite to give a substrate or piece thereof special properties such as oxidation resistance, flame retardant, hydrophobic or oleophobic, hardness, impermeability, or electrical or thermal insulation. It is intended to mean a partial or complete enclosure of the substrate by the object.

  The following examples further illustrate the present invention.

In the examples below, the silica sol used is an aqueous silica sol (“Levasil 300/300”) having a solids content of 30% by weight from BAYER and a particle size of 7-10 nm. The following abbreviations are also used in the examples:
MTEOS = methyltriethoxysilane
TEOS = tetraethoxysilane
PTEOS = phenyltriethoxysilane
ETEOS = ethyltriethoxysilane

Example 1
803 ml MTEOS and 223 ml TEOS are mixed and split in a ratio of 1: 1. Half of the silane mixture is stirred vigorously with 165 g of ZrO ₂ sol (SNZS-30A from Nissan Chemical) and mixed with 4.4 g of concentrated hydrochloric acid and after 5 minutes is mixed with the other half of the silane mixture.

  After a 12 hour post-reaction step, the binder is mixed vigorously with 10% by volume of water and stirred for an additional 5 minutes. Boron nitride having an average particle size of 1 μm is added to the resulting mixture in such an amount that 85% of the total solid content consists of boron nitride. The resulting material was spread on a glass plate with a thickness of about 0.5 mm. After drying for 12 hours at room temperature, the layer is removed and sintered as an independent standing body at 500 ° C. to give a rigid molded article.

Example 2
1. Sol preparation 16.7 ml of silica sol and 0.49 ml concentrated hydrochloric acid are added to a mixture of 65.4 ml MTEOS and 18.3 ml TEOS with vigorous stirring. After reaction of the silanes, the sol is cooled in an ice bath and filtered using a glass fiber filter (Schleicher and Schull, Rezist 40GF).

2. Use of the sol 100 g of glass gall globules are mixed with 20 ml of the sol and pressed in a 12 cm diameter press mold at a pressure of 4.4 MPa for 5 minutes. The part is then heated at 80 ° C. in a circulating air drying chamber for 8 hours. This gives a molded product that remains dimensionally stable at temperatures below the melting point of the raw material (the proportion of glass globules in the molded product is 6% by weight).

Reference example 1
1. Preparation of Standard Binder A The flask was charged with 655 g MTEOS and 191 g TEOS, and then 142 g aqueous silica sol and immediately followed by 9 ml H ₂ SO ₄ (40 wt%). Add with stirring. After about 1 minute of intense stirring, an exothermic reaction begins (temperature rises to about 60 ° C.). For aging, the dispersion is kept overnight at room temperature or refluxed for 1 hour for its subsequent use.

Preparation of standard binder B 621 g of MTEOS and 181 g of TEOS in a flask and then 185 g of aqueous silica sol (“Levasil 50/50”, SiO ₂ solid content 50% by weight, manufactured by BAYER ) And immediately afterwards 10.3 ml of H ₂ SO ₄ (40 wt%) is added to the resulting mixture with vigorous stirring. After about 1 minute of intense stirring, an exothermic reaction begins (temperature rises to about 60 ° C.). For aging, the dispersion is kept at room temperature overnight or refluxed for 1 hour and used for the next step.

Preparation of standard binder C Mixture that was charged to a flask with 463 g MTEOS, 180 g TEOS and 128 g dimethyldiethoxysilane, followed by 267 g aqueous silica sol and immediately 6.06 ml HCl (37 wt%). Add with vigorous stirring. After about 1 minute of intense stirring, an exothermic reaction begins (temperature rises to about 60 ° C.). The dispersion can be used directly after cooling it to room temperature.

Example 3
Production of rock wool molded parts Standard binder A (solids content: 35% by weight) is sprayed by spray gun onto untreated rock wool which is constantly stirred in a drum mixer. The proportion of binder is in the range of 3-12% by weight. After the spraying operation, the sample is molded at 150 ° C. in a heated press with a compression pressure of 0.5 t and a heating time of 20 minutes and a cooling time of 20 minutes. Thereby, a stable molded product is obtained.

Example 4
Preparation of pearlite combined heat removal board 6 g of water is added to 90 g of standard binder A having a solids content of 50% by weight and mixed vigorously with 300 g of pearlite (bulk density 5 l) in a drum mixer. The mixture is formed into a plate (15 cm × 15 cm × 5 cm) in a press. After their removal from the press, the plates are cured at 150 ° C. for 1 hour. In contrast to plates bonded with water glass, heat removal plates produced in this way show no cracking when subjected to various temperatures up to 1000 ° C.

Claims (13)

Particle shape, like cotton, Katakatachi, plate-shaped, foil-shaped, characterized by the nanocomposite in contact with the substrate and the substrate is selected from the group consisting of glass or mineral shape formed molded article, and a) colloidal Inorganic particles,
b) one or more general formulas (I)
R _x -Si-A _4-x (I)
[Where:
Group A is the same or different and one or more hydroxyl groups other than methoxy that can be removed hydrolytically, Group R is the same or different and cannot be removed hydrolytically, and x is 0, 1, 2 or 3, where x> 1 in at least 50 mol% of the silane]
Of the silane in a sol-gel process using 0.1 to 0.45 mole percent water per mole of hydrolyzable groups present, further hydrolysis and condensation of the microcomposite sol, A composite material that has been surface modified by activation of a microcomposite sol with the addition of water and subsequent curing.   The composite material according to claim 1, characterized in that the surface modification is carried out at a pH of 1-2 in the presence of an acid condensation catalyst.   The composite material according to claim 1 or 2, wherein the micro composite sol is subjected to a post-reaction at a temperature of room temperature to 120 ° C. From the group of colloidal inorganic particles are comprised of sol or dispersible powders sol and _SiO 2 of the _{minute, TiO 2, ZrO 2, Al} 2 O 3, Y 2 O 3, CeO 2, SnO 2, ZnO, iron oxides or carbon The composite material according to claim 1, wherein the composite material is selected.   Other additives (c) selected from the group consisting of curing catalysts, organic binders, pigments, dyes, flame retardants, glass forming element compounds, corrosion inhibitors and coating aids to produce microcomposite sols. The composite material according to claim 1, wherein the composite material is used.   6. Composite material according to any one of claims 1 to 5, characterized in that 5 to 60% by weight of colloidal inorganic particles are used for producing the microcomposites. 7. The composition according to claim 1, wherein 20 to 95% by weight of a polysiloxane represented by the formula R _x SiO 2 _(2-0.5x) is used to produce a _{microcomposite.} The composite material described in 1.   8. Composite material according to any one of claims 5 to 7, characterized in that no more than 20% by weight of other additives (c) are used to produce the microcomposites.   9. Composite according to any one of claims 1 to 8, characterized in that the surface modification is carried out using 0.25 to 0.45 mol% of water per mol of hydrolyzable groups present. material.   The composite material according to claim 1, wherein a weight ratio of the microcomposite is 0.1 to 80%.   The composite material according to claim 1, wherein curing is performed thermally. The composite material according to the radicals Shitsuma other coated with nanocomposite any one of claims 1 to 11 in the form of shaped articles comprising a matrix material that is integrated with nanocomposite.   The composite material according to claim 1, wherein the substrate is coated and / or integrated with a microcomposite.